<template>
  <!-- 商品分类导航 -->
  <div class="type-nav">
    <div class="container">
      <div @mouseenter="enterShow" @mouseleave="leaveShow">
        <h2 class="all">全部商品分类</h2>
        <!-- 过渡动画 -->
        <!-- <transition name="sort"> -->
        <div class="sort" v-show="show">
          <div class="all-sort-list2" @click="goSearch">
            <div class="hidden">
              <div :class="{cur:currentIndex==index}" class="item" v-for="(c1,index) in categoryList"
                :key="c1.categoryId">
                <h3 @mouseenter="changeIndex(index)">
                  <a href="javascript:;" :data-categoryName="c1.categoryName"
                    :data-category1Id="c1.categoryId">{{c1.categoryName}}</a>
                </h3>
                <div class="item-list clearfix">
                  <div class="subitem" v-for="(c2) in c1.categoryChild" :key="c2.categoryId">
                    <dl class="fore">
                      <dt>
                        <a href="javascript:;" :data-categoryName="c2.categoryName"
                          :data-category2Id="c2.categoryId">{{c2.categoryName}}</a>
                      </dt>
                      <dd>
                        <em v-for="(c3) in c2.categoryChild" :key="c3.categoryId">
                          <a href="javascript:;" :data-categoryName="c3.categoryName"
                            :data-category3Id="c3.categoryId">{{c3.categoryName}}</a>
                        </em>
                      </dd>
                    </dl>
                  </div>
                </div>
              </div>
            </div>

          </div>
        </div>
        <!-- </transition> -->

      </div>
      <nav class="nav">
        <a href="###">服装城</a>
        <a href="###">美妆馆</a>
        <a href="###">尚品汇超市</a>
        <a href="###">全球购</a>
        <a href="###">闪购</a>
        <a href="###">团购</a>
        <a href="###">有趣</a>
        <a href="###">秒杀</a>
      </nav>

    </div>
  </div>
</template>

<script>
  //引入mapState
  import {
    mapState
  } from "vuex"
  //引入lodash的节流
  import throttle from "lodash/throttle"
  export default {
    //全局组件
    name: "TypeNav",
    data() {
      return {
        //存储用户鼠标移上哪一个一级分类
        currentIndex: -1,
        //控制是否显示的变量
        show: true
      }
    },
    mounted() {
      //当组件挂载完毕
      //如果不是Home组件路由,将typeNav隐藏
      if (this.$route.path != "/home") {
        this.show = false
      }
    },
    methods: {
      //鼠标进入修改响应式数据currentIndex属性
      changeIndex: throttle(function (index) {
        this.currentIndex = index
      }, 50),
      //进行路由跳转的方法
      goSearch(event) {
        let element = event.target
        // console.log(element.dataset)
        //拿到节点身上的dataset属性
        let {
          categoryname,
          category1id,
          category2id,
          category3id
        } = element.dataset
        //如果标签身上有categoryName属性一定是a标签
        if (categoryname) {
          //一级分类,二三分类的a标签
          //整理路由跳转的参数
          let location = {
            name: "search"
          }
          let query = {
            categoryName: categoryname
          } //动态去添加
          if (category1id) {
            query.category1Id = category1id
          } else if (category2id) {
            query.category2Id = category2id
          } else {
            query.category3Id = category3id
          }
          //判断:如果路由跳转的时候  带有params参数,一起传递过去
          if (this.$route.params) {
            location.params = this.$route.params
            //整理完数据
            location.query = query
            //路由跳转
            this.$router.push(location)
          }


        }
      },
      //控制商品分类列表显示
      enterShow() {
        this.show = true
      },
      //控制商品分类列表隐藏
      leaveShow() {
        this.currentIndex = -1
        if (this.$route.path != "/home") {
          this.show = false
        }
      }
    },
    computed: {
      ...mapState({
        categoryList: (state) => {
          return state.home.categoryList.slice(0, 15)
        }
      })
    }
  }
</script>

<style lang="less" scoped>
  .type-nav {
    border-bottom: 2px solid #e1251b;

    .container {
      width: 1200px;
      margin: 0 auto;
      display: flex;
      position: relative;

      .all {
        width: 210px;
        height: 45px;
        background-color: #e1251b;
        line-height: 45px;
        text-align: center;
        color: #fff;
        font-size: 14px;
        font-weight: bold;
      }

      .nav {
        a {
          height: 45px;
          margin: 0 22px;
          line-height: 45px;
          font-size: 16px;
          color: #333;
        }
      }

      .sort {
        position: absolute;
        left: 0;
        top: 45px;
        width: 210px;
        height: 461px;
        position: absolute;
        background: #fafafa;
        z-index: 999;



        .all-sort-list2 {
          .item {
            h3 {
              line-height: 30px;
              font-size: 14px;
              font-weight: 400;
              overflow: hidden;
              padding: 0 20px;
              margin: 0;

              a {
                color: #333;
              }
            }

            .item-list {
              display: none;
              position: absolute;
              width: 734px;
              min-height: 460px;
              background: #f7f7f7;
              left: 210px;
              border: 1px solid #ddd;
              top: 0;
              z-index: 9999 !important;

              .subitem {
                float: left;
                width: 650px;
                padding: 0 4px 0 8px;

                dl {
                  border-top: 1px solid #eee;
                  padding: 6px 0;
                  overflow: hidden;
                  zoom: 1;

                  &.fore {
                    border-top: 0;
                  }

                  dt {
                    float: left;
                    width: 54px;
                    line-height: 22px;
                    text-align: right;
                    padding: 3px 6px 0 0;
                    font-weight: 700;
                  }

                  dd {
                    float: left;
                    width: 415px;
                    padding: 3px 0 0;
                    overflow: hidden;

                    em {
                      float: left;
                      height: 14px;
                      line-height: 14px;
                      padding: 0 8px;
                      margin-top: 5px;
                      border-left: 1px solid #ccc;
                    }
                  }
                }
              }
            }

            &:hover {
              .item-list {
                display: block;
              }
            }
          }

          .cur {
            background-color: skyblue;
          }
        }
      }

      //过渡动画的样式
      //过渡动画开始状态(进入)
      .sort-enter {
        height: 0px;
      }

      //过渡动画结束状态(进入)
      .sort-enter-to {
        height: 461px;
      }

      .sort-enter-active {
        transition: all .5s linear;
      }
    }
  }
</style>